The UK government on Friday defended an immigration raid that inflamed tensions in Glasgow's Muslim community at the start of Eid al-Fitr, insisting there was no connection to the Islamic festival.

Thursday's deportation raid targeted a property housing two illegal immigrants from India, who were not themselves believed to be Muslim.

A UK Home Office van was blockaded by hundreds of chanting protesters, and the pair were eventually released on bail as Glasgow police intervened in a bid to defuse tensions.

"The operation was routine and in no way connected to Eid. We are tackling illegal immigration and the harms it causes," Prime Minister Boris Johnson's official spokesman told reporters.

"We will continue to tackle illegal immigration," he added.

The area in Scotland's biggest city is home to a large Muslim community, and is part of the constituency of Scottish First Minister Nicola Sturgeon.

"The Home Office needs to ask itself hard questions," she said.

"Doing this on Eid, in the heart of our Muslim community, and in the midst of a serious Covid outbreak, was staggeringly irresponsible -- but the even deeper problem is an appalling asylum and immigration policy."

The incident came after Sturgeon's pro-independence party and allies secured a majority in the Edinburgh parliament in elections last week, and it fuelled anti-UK sentiment in sections of the Scottish media.

Friday's front-page headline on the pro-independence National newspaper read: "Glasgow 1 'Team UK' 0".

The raid also caused trouble for Britain's main opposition Labour party, after a prominent union official tweeted that London-born Home Secretary Priti Patel, who is of Indian descent, should herself be "deported".

Labour leaders suspended the Unite union's Howard Beckett, who apologised for the tweet but said he stood by his criticism of the government's "racist" policies.